Hi Bernard
I think that what you point out has far more than technical significance: I believe it's one of the factors that contributed to the star system existing and being sustained by legions of fans: believability.
You look at those candids of people like Gable and Marilyn, and what do you see? You see people. You do the same with contemporary movie/music people, and what do you see? You see plastic. And that's the difference: in the past you could empathise but now you simply can't: that closeness has been removed from the equation and you may as well be looking at a waxwork. There just isn't the humanity, the only thing that provides a bond beween the star and the public.
Now, it's only kids who follow anything/anybody, and that's good for five minutes. Who can be surprised? Was a time that adults were interested in stars just because they could see them as real, living similar, but richer, lives to themselves. You could see lines of maturity on faces, the look of pain or love in eyes. Now - it's all PS perfection even though it's actually nothing more than distortion. It must have been nice to work for Magnum or Globe in those days!
Rob C